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Hi John, Steve and I logged onto 'rime' yesterday to take a look. We setup a test set of REQUESTs to a completely unloaded real-server backend of our idd.unidata.ucar.edu cluster using port 80 for the traffic, and we experienced the same or worse latencies sending the NEXRAD3, NGRID, NIMAGE and NOTHER feeds to rime. The Port 80 test was to see if the problems you are seeing are specific to transfers using port 388, and the results are that they are not. The only thing we can think of trying on your end is moving the LDM queue to a RAM disk. We have seen two instances where moving the LDM queue to RAM disk has resulted in a dramatic drop in receipt latencies, so the test is worth a try. If you agree to proceed with this test, you will need to make a RAM disk (again, as 'root'), but you will need to make it about half as large as your current LDM queue (e.g., 4 GB insted of 7); change the LDM registry entries for location and size of the LDM queue (size so that it will fit in the RAM disk created); remake the LDM queue in the RAM disk; and then restart your LDM. Before creating a RAM disk (we couldn't do this as we would need 'root' access), a simple test is in order: run 'iotop' (needs to be run as 'root') and see if one or more 'ldmd' processes are showing very high use numbers. Please let us know if you are willing to do the RAM disk test. Again, we could do it for you if we had 'root' credentials on 'rime'. Comment: quite frankly, the RAM disk test should be understood as grasping at straws since we don't think that the problem is local to 'rime'. Cheers, Tom -- **************************************************************************** Unidata User Support UCAR Unidata Program (303) 497-8642 P.O. Box 3000 address@hidden Boulder, CO 80307 ---------------------------------------------------------------------------- Unidata HomePage http://www.unidata.ucar.edu **************************************************************************** Ticket Details =================== Ticket ID: GUQ-669331 Department: Support LDM Priority: Normal Status: Closed =================== NOTE: All email exchanges with Unidata User Support are recorded in the Unidata inquiry tracking system and then made publicly available through the web. If you do not want to have your interactions made available in this way, you must let us know in each email you send to us.